ObjectiveTo investigate the changes of activation of the abdominal muscles depending on exercise angles and whether the activation of rectus abdominis differs according to the location, during curl up and leg raise exercises, by measuring the thickness ratio of abdominal muscles using ultrasonography.MethodsWe examined 30 normal adults without musculoskeletal problems. Muscle thickness was measured in the upper rectus abdominis (URA), lower rectus abdominis (LRA), obliquus externus (EO), obliquus internus (IO), and transversus abdominis (TrA), at pre-determined angles (30°, 60°, 90°) and additionally at the resting angle (0°). Muscle thickness ratio was calculated by dividing the resting (0°) thickness for each angle, and was used as reflection of muscle activity.ResultsThe muscle thickness ratio was significantly different depending on the angles in URA and LRA. For curl up-URA p=0 (30°<60°), p=0 (60°>90°), p=0.44 (30°<90°) and LRA p=0.01 (30°<60°), p=0 (60°>90°), p=0.44 (30°>90°), respectively, by one-way ANOVA test-and for leg raise-URA p=0 (30°<60°), p=0 (60°<90°), p=0 (30°<90°) and LRA p=0.01 (30°<60°), p=0 (60°<90°), p=0 (30°<90°), respectively, by one-way ANOVA test-exercises, but not in the lateral abdominal muscles (EO, IO, and TrA). Also, there was no significant difference in the muscle thickness ratio of URA and LRA during both exercises. In the aspect of muscle activity, there was significant difference in the activation of RA muscle by selected angles, but not according to location during both exercises.ConclusionAccording to this study, exercise angle is thought to be an important contributing factor for strengthening of RA muscle; however, both the exercises are thought to have no property of strengthening RA muscle selectively based on the location.

ObjectiveTo compare transverse abdominis (TrA) contractility in stroke patients with hemiparesis and healthy adults using musculoskeletal ultrasonography.MethodsForty-seven stroke patients with hemiparesis and 25 age-matched healthy control subjects participated in this study. Stroke patients were divided into three groups on the basis of their degree of ambulation. Group A consisted of 9 patients with wheelchair ambulation, group B of 23 patients with assisted ambulation, and group C of 15 patients with independent ambulation. Inter-rater reliability regarding ultrasonographic measurement of abdominal muscle thickness in the control group was assessed by two examiners. The TrA contraction ratio (TrA contracted thickness/TrA resting thickness) was measured during abdominal drawing-in maneuver and was compared between the patients and the control group and between the ambulation groups.ResultsThe inter-rater reliability ranged from 0.900 to 0.947. The TrA contraction ratio was higher in the non-paretic side than in the paretic side (1.40±0.62 vs. 1.14±0.35, p<0.01). The TrA contraction ratio of the patient group was lower in the non-paretic side as well as in the paretic side than that of the control group (right 1.85±0.29, left 1.92±0.42; p<0.001). No difference was found between the ambulation regarding the TrA contraction ratio.ConclusionThe TrA contractility in hemiparetic stroke patients is significantly decreased in the non-paretic side as well as in the paretic side compared with that of healthy adults. Ultrasonographic measurement can be clinically used in the evaluation of deep abdominal muscles in stroke patients.

ObjectiveTo analyze the differences in the vertical ground reaction force (GRF) variables of hemiplegic patients compared with a control group, and between the affected and unaffected limbs of hemiplegic patients using foot scans.MethodsPatients (n=20) with hemiplegia and healthy volunteers (n=20) underwent vertical force analysis. We measured the following: the first and second peak forces (F1, F2) and the percent stances at which they occurred (T1, T2); the vertical force impulse (VFI) and stance times. The GRF results were compared between the hemiplegic patients and control individuals, and between the affected and unaffected limbs of hemiplegic patients. Additionally, we analyzed the impulse of the unaffected limb according to the motor assessment scale (MAS), Brunnstrom stage, and a Timed Up and Go Test.ResultsThe F1s and F2s of the affected and unaffected limbs were significantly less than those of the normal control individuals (p<0.05). The T1s of both the affected and unaffected limbs of the patients were greater than control individuals, whilst the T2s were lower (p<0.05). Greater impulses and stance times were recorded on both sides of the patients than in the limbs of the control individuals (p<0.05). The MAS, Brunnstrom stage and Timed Up and Go Test results were significantly correlated with the VFI of the unaffected limbs (p<0.05).ConclusionThe high impulse values of the unaffected limb were associated with complications during gait rehabilitation. Therefore, these results suggest that unaffected limbs should also be taken into consideration in these patients.